Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/Documentation/sphinx/kernellog.py b/Documentation/sphinx/kernellog.py
new file mode 100644
index 0000000..af924f5
--- /dev/null
+++ b/Documentation/sphinx/kernellog.py
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Sphinx has deprecated its older logging interface, but the replacement
+# only goes back to 1.6.  So here's a wrapper layer to keep around for
+# as long as we support 1.4.
+#
+import sphinx
+
+if sphinx.__version__[:3] >= '1.6':
+    UseLogging = True
+    from sphinx.util import logging
+    logger = logging.getLogger('kerneldoc')
+else:
+    UseLogging = False
+
+def warn(app, message):
+    if UseLogging:
+        logger.warning(message)
+    else:
+        app.warn(message)
+
+def verbose(app, message):
+    if UseLogging:
+        logger.verbose(message)
+    else:
+        app.verbose(message)
+
+